I want to check if a RIC is a primary instrument. For that, I usually use the formula TR.IsPrimaryInstrument (with a boolean output). Let's suppose I use this RIC: 00XJ.F, the outcome for this ticker and TR.IsPrimaryInstrument is 'true'.

But, when I use TR.IsPrimaryInstrument for a similar RIC (00XJ.DE) I get back that it is also a 'true' outcome to the same formula.

How is this possible? I would like to understand.

For example, when I check the RIC associated to other ID's, like ISIN, using TR.PrimaryInstrument, I get 00XJ.DE and not 00XJ.F

What should I use to define my criteria on primariness using these Eikon formulas? I'm a bit confused over this.

Thanks in advance for any guidance!